This invention relates to furnaces having one or more burners which provide heat to one or more heat exchangers. In particular, this invention relates to a method and apparatus for shielding a person in the immediate vicinity of the furnace from the sound produced by the one or more burners.
The burners of modern day furnaces provide significant amounts of heat to one or more heat exchangers within the furnace. In order to do so, the burners must draw in significant amounts of air into the burner chamber. The drawn in air mixes with fuel that is introduced into the burners and ignited. The result is a high quality flame that often also produces a significant amount of noise.
The air is typically drawn through slotted vents in a removable door for the furnace that is positioned in front of the burner chamber. It has heretofore not been deemed appropriate to place any significant obstruction between the slotted vents in the door and the burner chamber. This has however sometimes led to a high level of noise being emitted through the slotted vents due to the intense burning of the fuel by the burners. Such noise levels can be disconcerting to anyone in the immediate vicinity of the furnace. It would be preferable if a person in the vicinity of the furnace could be shielded from these noise levels.
The present invention provides a furnace with a sound shield positioned between burners located within a burner chamber of a furnace and the portion of the furnace immediately in front of the burner chamber. This latter portion of the furnace is typically a removable door having slotted vents that allow air to be drawn into the burner chamber. The sound shield is positioned between the slotted vents and the burner chamber in such a manner so as to prevent substantial amounts of burner noise being produced by burning fuel from escaping through the vents. This is done without unduly restricting the flow of air through the slotted vents to the burners.
In a preferred embodiment, the sound shield is attached to the rear of the removable door at a distance from the slotted vents in the door. The sound shield preferably extends both above and below the burners so as to directly interfere with the sound wave propagations from the burners when fuel is being burned. In another embodiment, this sound shield extends into the furnace so as to be closer to the burners.
In yet another embodiment, the sound shield is attached to the body of the furnace instead of the removable door. The sound shield preferably extends both above and below the burners so as to provide a direct interference barrier to the sound wave propagations from the burners when fuel is being burned. This sound shield may either be flat against the body of the furnace or alternatively may extend into the interior of the furnace or into the interior of the removable door.
In yet still another embodiment, the sound shield may be attached to the burner chamber structure as opposed to the body of the furnace. In this latter case, the widthwise dimension of the sound shield need not span the entire width of the furnace body.